Process for the Preparation of Umeclidinium Bromide

ABSTRACT

The present invention discloses processes comprising a) reacting ethyl isonipecotate with 1-bromo-2-chloroethane in the presence of an organic base in a solvent to form ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) or a salt thereof. Process step a) may be included in a process for preparing umeclidinium bromide that comprises further process steps: b) reacting ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) or a salt thereof with lithium diisopropylamide in a solvent to form ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III); c) reacting ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III) with phenyl lithium in a solvent to form 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV); and d) reacting 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV) with ((2-bromoethoxy)methyl) benzene in a solvent to form 4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]octane bromide (I), umeclidinium bromide. A process comprising d) reacting 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol with ((2-bromoethoxy)methyl) benzene in a solvent to form 4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]octane bromide (I), umeclidinium bromide, wherein the solvent is selected from cyclic ethers such as tetrahydrofuran, aromatic solvents, such as toluene, ketones such as acetone and protic solvents such as water or combinations thereof, optionally wherein the solvent is water is also disclosed. Umeclidinium bromide obtainable from the disclosed processes, ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) and pharmaceutical compositions are also disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 16/349,404 filed May 13, 2019, published as U.S.Patent Application Publication No. US 2019/0263814 A1 and entitled“Process for the Preparation of Umeclidinium Bromide” which is a filingunder 35 U.S.C. 371 of International Application No. PCT/GB2017/053396filed Nov. 10, 2017, entitled “Process for the Preparation ofUmeclidinium Bromide” which claims priority to Portuguese PatentApplication No. 109740 filed Nov. 14, 2016, which applications areincorporated by reference herein in their entirety.

FIELD OF INVENTION

The present invention relates to novel processes for the preparation of4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]octanebromide, a compound known by the name umeclidinium bromide.

Umeclidinium bromide is an effective anticholinergic agent and has beenused in the treatment of respiratory diseases such as asthma or chronicobstructive pulmonary disease (COPD). It is used for preparingpharmaceutical compositions to be administrated as a dry powder for oralinhalation at once-daily micrograms dose. New compositions,combinations, forms of administration (e.g. metered-dose inhalers) anddosages using umeclidinium bromide are being developed.

BACKGROUND OF THE INVENTION

The compound umeclidinium bromide of molecular structure (I) depictedbelow is a long-acting muscarinic antagonist used in the treatment ofairflow obstruction in patients with chronic obstructive pulmonarydisease (COPD), including chronic bronchitis and emphysema.

The synthesis of umeclidinium bromide has been claimed in WO2005/104745involving four steps as follows:

The key intermediate ethyl 1-(2-chloroethyl)piperidine-4-carboxylate offormula (II) is synthesized by reacting 1-bromo-2-chloroethane and ethylisonipecotate in the presence of potassium carbonate in acetone.However, the compound of formula (II) is prepared in very low yields(39%), due to the formation of a dimer by-product, diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V), which must beseparated from the primary compound by chromatographic techniques.

In order to overcome the dimerization issue and consequent low yields,WO2014/027045 claims an alternative two-step process for the preparationof the compound of formula (II) in better yield (80%) as follows:

There is no doubt that such synthetic alternative can lead to betteryields, but the need for two reaction steps, instead of a single one asdescribed in WO2005/104745, is not the best solution for an industrialapplication. Additionally, WO2014/027045 discloses the use of a hightemperature in the first step and the use of a highly corrosive andtoxic reagent in the second step, namely thionyl chloride that producesenvironmentally unfriendly SOx by-products. Three major disadvantageswhen compared to the mild conditions described in WO2005/104745.

Alternatively, WO2016/071792 claims a one-step process for thepreparation of compound of formula (II) which comprises the reaction ofethyl isonipecotate with halogenated-acetaldehyde in a mixture ofmethanol:acetic acid together with a reducing agent as follows:

Although leading to better yields (90%) in comparison to those describedin WO2005/104745 and WO2014/027045, the synthesis requires the use ofmethanolic-aqueous acidic solutions, which can degrade the ester moietyto some extent, prior to the reaction with the reductive agents.

WO2011/029896 describes an alternative process to prepare umeclidiniumbromide through the use of different intermediates as follows:

wherein P is a protecting group; R is selected from the group consistingof alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocycle, aryland heteroaryl; and X and Y are leaving groups, provided that X and Yare different.

However, this process is more complex than the process disclosed inWO2005/104745 because it encompasses a longer synthetic route andincludes extra protection-deprotection steps.

Unsolvated crystalline forms of umeclidinium bromide have been disclosedas polymorphs of the active pharmaceutical ingredient (WO2014/027045,U.S. Pat. No 9,273,001 B2), showing that the compound may give rise to avariety of solids having distinct physical properties. The preparationof pure umeclidinium bromide in a single crystalline form has been achallenge for the industry as umeclidinium bromide is highly susceptibleto forming solvates. Umeclidinium bromide solvates include a methanolsolvate (CZ27764 (Sanofi)), and ethanol, 2-propanol,2-methylpropan-1-ol, chlorobenzene and p-xylene solvates have beendisclosed (WO2014/027045, U.S. Pat. No. 9,273,001 B2). 1-Propanol hasbeen used as the solvent in the final process step to minimize solvateformation (U.S. Pat. No. 9,273,001 B2) avoiding the resuspension of thecompound in ethyl acetate, methanol and water, which was previouslyrequired (example 84, Method B, WO2005/104745).

In order to fulfill the umeclidinium bromide market demand, there is aneed to develop more efficient processes. Namely, processes that offeradvantages over those previously disclosed in WO2016/071792,WO2005/104745, WO2014/027045 and WO2011/029896. There is also a need toprovide processes that prepare umeclidinium bromide in a single, purecrystalline form with a consistent level of crystallinity and chemicalpurity.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided aprocess for preparing umeclidinium bromide comprising:

-   -   a) reacting ethyl isonipecotate with 1-bromo-2-chloroethane in        the presence of an organic base in a solvent to form ethyl        1-(2-chloroethyl)piperidine-4-carboxylate (II) or a salt        thereof;    -   b) reacting ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II)        or a salt thereof with lithium diisopropylamide in a solvent to        form ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III);    -   c) reacting ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III)        with phenyl lithium in a solvent to form        1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV); and    -   d) reacting 1 -azabicyclo [2.2.2]        oct-4-yl(diphenyl)methanol (IV) with ((2-bromoethoxy)methyl)        benzene in a solvent to form        4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo        [2.2.2] octane bromide (I), umeclidinium bromide.

According to another aspect of the present invention, there is provideda process comprising:

-   -   a) reacting ethyl isonipecotate with 1-bromo-2-chloroethane in        the presence of organic base in a solvent to form ethyl        1-(2-chloroethyl)piperidine-4-carboxylate (II) or a salt        thereof.

According to a further aspect of the present invention, there isprovided a process comprising:

-   -   d) reacting 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol with        ((2-bromoethoxy)methyl) benzene in a solvent to form        4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]        octane bromide (I), umeclidinium bromide, wherein the solvent is        selected from a group of cyclic ethers such as tetrahydrofuran,        aromatic solvents, such as toluene, ketones such as acetone and        protic solvents such as water or combinations thereof,        optionally wherein the solvent is water.

Other aspects of the invention relate to ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II) and umeclidinium bromideobtainable by the processes of the present invention, and pharmaceuticalcompositions comprising said umeclidinium bromide.

Surprisingly, it has been found that step a) of the present inventionaffords the key intermediate ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II) in higher yields (66%)than the process disclosed in WO2005/104745 without needing to increasethe number of process steps (such as protection-deprotection steps),without needing to use high temperatures and without needing to useundesirable reagents (such as corrosive reagents, toxic reagents ormethanol/aqueous acidic systems). Step a) of the present inventioncontrols the formation of undesirable by-products such as diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V). Ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II) obtained during step a)of the present invention can be either purified or used directly in theprocess steps that follow without purification (e.g. purification bychromatography). The processes of the present invention enable atelescoped (or one-pot) synthesis of umeclidinium bromide, whereby thestarting material is subjected to successive chemical reactions. Such asynthesis is in great demand because it improves chemical reactionefficiency by avoiding separation and purification of intermediates,thereby saving time and resources whilst increasing chemical yield.

One advantage of step a) of the present invention is that use of theethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) intermediateobtained from this process step allows the preparation of umeclidiniumbromide in a single, pure crystalline form with a consistent level ofcrystallinity and chemical purity.

Additionally, it has been found that step d) of the present inventionaffords a product with a single, pure crystalline form with a consistentlevel of crystallinity and chemical purity. Therefore, one furtheradvantage of the process of the present invention is that theumeclidinium bromide obtained during step d) of the present invention isa single, pure crystalline form with a consistent level of crystallinityand chemical purity.

Consequently, the present invention discloses processes for thepreparation of umeclidinium bromide which afford a single, purecrystalline form with a consistent level of crystallinity and chemicalpurity.

Finally, the processes of the present invention enable the production ofumeclidinium bromide with a particle size suitable for inhalation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: XRPD diffractogram of umeclidinium bromide obtained from Example18.

FIG. 2: DSC thermogram of umeclidinium bromide obtained from Example 18.

FIG. 3: TGA thermogram of umeclidinium bromide obtained from Example 18.

FIG. 4: HPLC of umeclidinium bromide obtained from Example 18.

FIG. 5: HPLC of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV)obtained after three steps of Example 19 and used as the startingmaterial in the final step to prepare umeclidinium bromide.

FIG. 6: HPLC umeclidinium bromide recrystallized from water from Example20.

FIG. 7: XRPD umeclidinium bromide before micronization.

FIG. 8: XRPD umeclidinium bromide after fluid energy jet millmicronization from Example 21.

FIG. 9: XRPD umeclidinium bromide after high pressure homogenizationmicronization from Example 22.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides alternative processes for preparingumeclidinium bromide and one of the key intermediates in preparingumeclidinium bromide, namely ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II).

The present invention may provide a process comprising the followingsteps:

-   -   a) reacting ethyl isonipecotate with 1-bromo-2-chloroethane in        the presence of an organic base in a solvent to form ethyl        1-(2-chloroethyl)piperidine-4-carboxylate (II) or a salt        thereof;    -   b) reacting ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II)        or a salt thereof with lithium diisopropylamide in a solvent to        form ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III);    -   c) reacting ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III)        with phenyl lithium in a solvent to form        1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV);    -   d) reacting 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV)        with ((2-bromoethoxy)methyl) benzene in a solvent to form        4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]octane        bromide (I), umeclidinium bromide in a single, pure crystalline        form and optionally;    -   e) recrystallizing umeclidinium bromide to consistently obtain a        high purity product and optionally;    -   f) micronizing umeclidinium bromide to obtain a product with a        particle size suitable for inhalation while maintaining its        crystalline form.

Steps a) to e) may be combined in the absence of step f). Steps a) to d)and f) may be combined in the absence of step e).

Steps d) and e) may be combined in the absence of the other processsteps. Steps d) and f) may be combined in the absence of the otherprocess steps. Steps d), e) and f) may be combined in the absence of theother process steps.

Step a) of the present invention may be carried out as follows:

-   -   a) reacting ethyl isonipecotate with 1-bromo-2-chloroethane in        the presence of an organic base in a solvent, at a temperature        between about 20° C. to about 56° C., to form ethyl        1-(2-chloroethyl)piperidine-4-carboxylate (II); and preferably        thereafter (i) performing solvent exchange, removing any salts        formed from the reaction mixture, preferably by aqueous        extraction, and concentrating the resulting solution to isolate        the ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) present        from solution after filtration to remove the dimer; or        thereafter (ii) removing any salts formed from the reaction        mixture, preferably by aqueous extraction, acidification of the        resulting solution with inorganic or organic acids, preferably        hydrochloric acid, acetic acid, succinic acid or oxalic acid and        isolating the product ethyl        1-(2-chloroethyl)piperidine-4-carboxylate (II) as a salt,        preferably by filtration and drying.

The solvent used in step a) may be selected from the group consisting ofketones such as acetone.

The organic base used in step a) may be selected from the groupconsisting of organic bases such as amines like triethylamine, pyridine,N,N-diisopropylethylamine, 4-(dimethylamino)pyridine,1,8-diazabicyclo[5.4.0]undec-7-ene. Preferably the organic base istriethylamine. Upon completion of the reaction of step a), solventexchange may be performed, triethylamine salts can be removed by aqueousextraction, and the resulting solution can be concentrated to isolatethe ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II). By usingtriethylamine as the organic base, it is possible to obtain ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II) in yields up to 66% witha residual content of diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V) below 14%. Incontrast, by performing the innovator's procedure disclosed inWO2005/104745, the formation of by-product diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V) reached 22%.

Step a) may be carried out at a temperature between about 20° C. andabout 56° C., preferably between about 20° C. and about 30° C., morepreferably the reaction is performed at a temperature between about 20°C. and about 25° C. At temperatures higher than 30° C. more significantamounts of the byproduct diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V) are obtainedyielding ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II) in loweryield (34%) Step a) may be carried out for a time period of betweenabout 14 h and about 24 h.

After any salts (e.g. triethylamine salts) have been removed by aqueousextraction, the resulting solution can be acidified with inorganic ororganic acids, preferably using hydrochloric acid, acetic acid, succinicacid or oxalic acid or solutions thereof, and the product ethyl1-(2-chloroethyl)piperidine-4-carboxylate (II) can be isolated as asalt, preferably by filtration and drying.

As disclosed above, step a) may comprise exchanging the reactionsolvent. The exchange solvent may comprise one or more alkanes, such asn-heptane or a mixture of heptanes.

As also disclosed above, step a) may comprise removing the dimer byfiltration. The reaction mixture may be cooled prior to filtration,optionally being cooled down to about −20° C. and maintained at thattemperature for about 12 h to about 24 h, optionally for about 16 h.

In combination, step a) may comprise:

-   -   i) exchanging the reaction solvent;    -   ii) aqueous extraction; and    -   iii) removing the dimer by filtration.

Step b) of the present invention may be carried out as follows:

-   -   b) reacting ethyl 1-(2-chloroethyl)piperidine-4-carboxylate (II)        or a salt thereof with lithium diisopropylamide in a solvent,        preferably at a temperature between about −50° C. and about        25° C. to form ethyl        1-azabicyclo[2.2.2]octane-4-carboxylate (III) or a salt thereof;        and preferably thereafter removing any salts formed from the        reaction mixture, preferably by basic aqueous extraction, and        performing solvent distillation and solvent exchange.

The solvent used in step b) may be selected from the group consisting ofcyclic ethers such as tetrahydrofuran (THF).

Step c) of the present invention may be carried out as follows:

-   -   c) reacting ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III)        or a salt thereof with phenyl lithium in a solvent, preferably        at a temperature between about −30° C. to about 25° C. to form        1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV) or a salt        thereof; preferably treating the reaction mixture containing        1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV) or a salt        thereof with water and concentrating the resulting solution, and        preferably thereafter adding a suitable anti-solvent to effect        precipitation, and isolating the product so formed, preferably        by filtration and drying, with a purity of ≥98.0% by HPLC.

The solvent used in step c) may be selected from the group consisting ofcyclic ethers such as THF.

Step d) of the present invention may be carried out as follows:

-   -   d) reacting 1-azabicyclo [2.2.2] oct-4-yl(diphenyl)methanol (IV)        with ((2-bromoethoxy)methyl) benzene in a solvent, at a        temperature between about 40° C. and about solvent reflux        temperature, preferably at a temperature between about 60° C.        about solvent reflux temperature to form        4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo        [2.2.2] octane bromide (I), umeclidinium bromide, and preferably        cooling down the reaction mixture to a temperature between about        −10° C. and about 5° C., preferably stirring the suspension at a        temperature between about −10° C. and about 5° C. for about 2 h.        Thereafter, the resulting product can be isolated, preferably by        filtration and dried at a temperature of between about 35° C.        and about 55° C., preferably under vacuum, with a purity of        ≥98.0% by HPLC, in a single crystalline form.

The solvent used in step d) may be selected from the group consisting ofcyclic ethers such as THF, aromatic solvents, such as toluene, ketonessuch as acetone, and protic solvents such as water. Step d) may becarried out at a temperature between about 40° C. and about 111° C.,preferably optionally between about 60° C. and about 100° C. Preferablythe reaction is carried out in water at a temperature between about 60°C. to about 100° C. Step d) may be carried out for a time period ofbetween about 18 h to about 24 h. When the reaction is complete, coolingdown the reaction allows umeclidinium bromide to be obtained in yieldsup to 84%. The purity of the product obtained by following the proceduredescribed is typically ≥98.0% by HPLC, in a single crystalline form. Thecrystalline form of the isolated umeclidinium bromide is an unsolvatedform of umeclidinium bromide.

Step e) of the present invention may be carried out as follows:

-   -   e) recrystallizing the umeclidinium bromide in a solvent, at a        temperature between about 40° C. to about solvent reflux        temperature, preferably at a temperature between about 60° C. to        about 80° C. to obtain        4-[hydroxyl(diphenyl)methyl]-1-[2-(phenylmethyl)oxy]ethyl]-1-azoniabicyclo[2.2.2]octane        bromide (I), umeclidinium bromide, and preferably cooling down        the reaction mixture to a temperature between about −10° C. and        about 5° C., preferably stirring the suspension at a temperature        between about −10° C. and about 5° C. for about 2 h. Thereafter,        the resulting product is isolated, preferably by filtration and        dried at a temperature of between about 35° C. and about 55° C.,        preferably under vacuum, to provide a product with a purity of        ≥99.0% by HPLC and in a single crystalline form.

Umeclidinium bromide obtained according to the step d) of the presentinvention can be recrystallized. The recrystallization solvents may beselected from the group consisting of alcohols, such as 1-propanol,protic solvents such as water or mixtures of both classes of solvents.Preferably recrystallization is carried out in water, optionally bysuspending the material in water at a temperature between about 40° C.to about solvent reflux temperature, preferably at a temperature betweenabout 60° C. and about 80° C. The resulting solution may be cooled to atemperature between about −10° C. and about 5° C. and the resultingsuspension may be stirred at a temperature between about −10° C. andabout 5° C. for about 2 hours. Preferably, umeclidinium bromide isisolated (optionally by filtration), washed with water (optional) andthen dried. The umeclidinium bromide may be dried under vacuum at atemperature between about 35° C. and about 55° C. The dried producttypically has a purity ≥99.0% by HPLC and exhibits a single crystallineform.

The X-Ray Powder Diffraction (XRPD) diffractogram, the DifferentialScanning Calorimetry (DSC) thermogram, the Thermogravimetric Analysis(TGA) thermogram and HPLC chromatogram of a product obtained accordingto the present invention are presented in FIGS. 1-9.

Umeclidinium bromide obtained from the present invention is preferablymicronized to obtain material with a particle size suitable forinhalation. Therefore, the present invention also provides amicronization process for tailoring the particle size whilst maintainingthe crystalline form of umeclidinium bromide.

EXAMPLES

The following examples are provided to illustrate the process of thepresent invention and are not intended to be construed as limitations ofthe present invention; minor variations may be resorted to withoutdeparting from the spirit and scope of the present invention.

Example 1 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

Triethylamine (1.09 mL, 7.79 mmol) was added to a solution of ethylisonipecotate (0.80 mL, 5.19 mmol) in acetone (7.20 mL) followed by1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). The reaction mixture wasstirred for 24 h at 25° C. and then concentrated under vacuum. Theresulting residue was treated with water (3.0 mL) and extracted withethyl acetate (3×3.0 mL). The combined organic layers were dried withMgSO₄, filtered and concentrated under vacuum. The purification of thecrude product was performed by flash chromatography on silica gel(gradient 1:1 n-hexane/ethyl acetate to 9:1 ethyl acetate/methanol)resulting in the desired compound (colorless liquid, 0.75 g, 65.6%) andthe respective dimer (0.25 g, 14.0%).

Ethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II): ¹H-NMR (300MHz, CDCl₃) δ 4.11 (q, J=5.3 Hz, 2H), 3.55 (t, J=4.0 Hz, 2H), 2.88-2.84(m, 2H), 2.68 (t, J=4.0 Hz, 2H), 2.24 (dt, J=12.0, 3.0 Hz, 1H), 2.12(td, J=11.3, 2.7 Hz, 2H), 1.93-1.65 (m, 4H), 1.22 (t, J=9.0 Hz, 3H);¹³C-NMR (75 MHz, CDCl₃) δ 175.11 60.51, 60.21, 53.18, 41.23, 41.09,28.29, 14.38. MS (ESI) calculated for C₁₀H₁₈ClNO²: 219, found 220[M+H]⁺.

Diethyl 1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V): ¹H-NMR(300 MHz, CDCl₃) δ 4.11 (q, J=5.25 Hz, 4H), 2.99-2.76 (m, 4H), 2.47 (s,4H), 2.30-2.20 (m, 2H), 2.07-1.99 (m, 6H), 1.90-1.84 (m, 4H), 1.79-1.66(m, 4H), 1.23 (t, J=6.0 Hz, 6H); ¹³C-NMR (75 MHz, CDCl₃) δ 175.29,60.49, 56.43, 53.68, 41.29, 28.40, 14.40. MS (ESI) m/z calcd forC₁₈H₃₂N₂O₂: 340, found 341 [M+H]⁺.

Example 2 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

Triethylamine (1.09 mL, 7.79 mmol) was added to a solution of ethylisonipecotate (0.80 mL, 5.19 mmol) in acetone (8.60 mL) followed by1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). The reaction mixture wasstirred for 17 h at 25° C. n-heptane (8.6 mL) was then added and theacetone was removed under vacuum. To the resultant mixture, n-heptane(8.6 mL) was added again and more acetone was removed under vacuum toobtain a volume of 8.6 mL. Water (8.6 mL) was added to the mixture andextracted with n-heptane (2×8.6 mL). The combined organic layers weredried with MgSO₄, filtered and concentrated under vacuum. Furthern-heptane was added (2.40 mL) and the solution was placed at 0° C. for 1h and cooled down to −20° C. for 16 h. The solution was filtered toremove dimer (diethyl1,1′-(ethane-1,2-diyl)bis(piperidine-4-carboxylate) (V)) and thenconcentrated under vacuum. The purification of the crude product wasperformed by flash chromatography on silica gel (gradient 1:1n-hexane/ethyl acetate to 9:1 ethyl acetate/methanol) resulting in thedesired compound (colorless liquid, 0.63 g, 55.1%) and the respectivedimer (0.10 g, 5.8%).

Example 3 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

A solution of ethyl isonipecotate (0.40 mL, 2.60 mmol) and triethylamine(0.55 mL, 3.90 mmol) in acetone (1.3 mL) was slowly added over 5 h to asolution of 1-bromo-2-chloroethane (0.43 mL, 5.19 mmol) in acetone (3.0mL) at 56° C. The reaction mixture was stirred for 24 h at 56° C. andthen concentrated under vacuum. The resulting residue was treated withwater (1.0 mL) and extracted with diethyl ether (3×3.0 mL). The combinedorganic layers were dried with MgSO₄, filtered and concentrated undervacuum. The purification of the crude product was performed by flashchromatography on silica gel 6:4 n-hexane/ethyl acetate) resulting inthe desired compound (colorless liquid, 0.19 g, 33.5%) and therespective dimer.

Example 4 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

A solution of ethyl isonipecotate (0.40 mL, 2.60 mmol) and triethylamine(0.55 mL, 3.90 mmol) in acetone (1.6 mL) was slowly added over 5 h to asolution of 1-bromo-2-chloroethane (0.86 mL, 10.38 mmol) and potassiumiodide (10%, 1.04 mmol, 0.17 mg) in acetone (7.0 mL) at roomtemperature. The reaction mixture was stirred for 24 h at 25° C. andthen concentrated under vacuum. The resulting residue was treated withwater (1.0 mL) and extracted with diethyl ether (3×3.0 mL). The combinedorganic layers were dried with MgSO₄, filtered and concentrated undervacuum. The purification of the crude product was performed by flashchromatography on silica gel (6:4 n-hexane/ethyl acetate) resulting inthe desired compound (colorless liquid, 0.29 g, 50.1%) and therespective dimer.

Example 5 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

N,N-diisopropylethylamine (DIPEA) (1.36 mL, 7.79 mmol) was added to asolution of ethyl isonipecotate (0.80 mL, 5.19 mmol) in acetone (8.60mL) followed by 1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). Thereaction mixture was stirred for 24 h at 25° C. Water (3.0 mL) was thenadded, the pH was neutralized with HCl (1M) and the aqueous phase wasextracted with diethyl ether (3×10.0 mL). The combined organic layerswere dried with MgSO₄, filtered and concentrated under vacuum. The crudeproduct (0.67 g) was analyzed by ¹H-NMR resulting in a 1.00:0.06 ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) to dimer.

Example 6 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

4-dimethylaminopyridine (DMAP) (0.95 g, 7.79 mmol) was added to asolution of ethyl isonipecotate (0.80 mL, 5.19 mmol) in acetone (8.60mL) followed by 1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). Thereaction mixture was stirred for 24 h at 25° C. Water (3.0 mL) was thenadded, the pH was neutralized with HCl (1M) and the aqueous phase wasextracted with diethyl ether (3×10.0 mL). The combined organic layerswere dried with MgSO₄, filtered and concentrated under vacuum. The crudeproduct (0.52 g) was analyzed by ¹H-NMR resulting in a 1.00:0.06 ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) to dimer.

Example 7 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

1,8-diazabicycloundec-7-ene (DBU) (1.16 mL, 7.79 mmol) was added to asolution of ethyl isonipecotate (0.80 mL, 5.19 mmol) in acetone (8.60mL) followed by 1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). Thereaction mixture was stirred for 24 h at 25° C. Water (3.0 mL) was thenadded, the pH was neutralized with HCl (1M) and the aqueous phase wasextracted with diethyl ether (3×10.0 mL). The combined organic layerswere dried with MgSO₄, filtered and concentrated under vacuum. The crudeproduct (0.88 g) was analyzed by ¹H-NMR and the dimer was not detected.

Example 8 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)

Pyridine (0.63 mL, 7.79 mmol) was added to a solution of ethylisonipecotate (0.80 mL, 5.19 mmol) in acetone (8.60 mL) followed by1-bromo-2-chloroethane (0.86 mL, 10.38 mmol). The reaction mixture wasstirred for 24 h at 25° C. n-heptane (8.6 mL) was then added and theacetone was removed under vacuum. To the resultant mixture, n-heptane(8.6 mL) was added again and more acetone was removed under vacuum toobtain a volume of 8.6 mL. Water (8.6 mL) was added to the mixture andextracted with n-heptane (2×8.6 mL). The combined organic layers weredried with MgSO₄, filtered and concentrated under vacuum. The crudeproduct (0.38 g) was analyzed by 1H-NMR resulting in 1.00:0.10 ratio ofethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) to dimer.

Example 9 Preparation of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate hydrochloride

To a solution of ethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)(0.15 mL) in ethyl acetate (2 mL) was added hydrogen chloride (1.25 M)in ethanol (0.72 mL), drop by drop, at room temperature. The solvent wasremoved under vacuum, resulting in a crystalline white solid.

Example 10 Preparation of ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate(III)

A solution of ethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II)(5.0 g, 22.76 mmol) in tetrahydrofuran (THF, 147.0 mL) was cooled downto −50° C. under nitrogen. LDA (2.0 M in heptane/THF/ethyl benzene, 17.0mL, 34.0 mmol) was added to the solution at −50° C. over 25 mins. Thereaction mixture was allowed to warm up to room temperature over 16 h.The reaction was quenched with saturated aqueous K₂CO₃ (122.0 mL) andextracted with diethyl ether (3×120.0 mL). The combined organic layerswere dried with Mg_(S)O₄, filtered and concentrated under vacuum. Theresulting orange liquid was co-evaporated three times withdichloromethane to remove excess ethyl benzene, resulting in an orangeoil (4.15 g, 99.4%). Ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate(III): ¹H-NMR (300 MHz, CDCl₃) δ 4.10 (t, J=5.23 Hz, 2H), 2.90-2.85 (m,6H), 1.71-1.66 (m, 6H), 1.22 (t, J=4.0 Hz, 3H).

Example 11 Preparation of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol(IV)

A solution of phenyllithium (1.9 M in 70 cyclohexane/30 ether, 22.30 mL,42.40 mmol) was cooled down to −30° C. under nitrogen. A solution ofethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III, 2.0 g, 10.90 mmol)in THF (27.0 mL) was slowly added to the reaction mixture at −30° C.over 25 mins. The reaction mixture was allowed to warm up to roomtemperature over 16 h. The reaction was quenched with water (10.0 mL)and then evaporated to dryness under vacuum. Water (40.0 mL) and ethylacetate (40.0 mL) were added, causing a white solid to crash out. Thissolid was filtered off under vacuum, to give a white powder (2.46 g,76.8%). 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV): ¹H-NMR (300MHz, CDCl₃) δ 7.54-7.51 (m, 3H), 7.33-7.20 (m, 6H), 2.85-2.80 (m, 6H),1.78-1.72 (m, 6H). MS (ESI) m/z calcd for C₂₀H₂₃NO: 293, found 294[M+H]+.

Example 12 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a solution of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV, 0.20g, 0.69 mmol) in THF (30.0 mL) was added ((2-bromoethoxy)methyl)benzene(0.16 mL, 1.03 mmol). The solution was stirred for 24 h at 60° C. Thenthe solution was cooled down to 25° C. and concentrated under vacuum,forming a white solid. The product was filtered and washed with ethylacetate (5×20.0 mL) and n-hexane (5×20.0 mL) under vacuum. The whitesolid was then dried under vacuum (0.30 g, 82.2%).

4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I): ¹H-NMR (300 MHz, DMSO-d₆) δ 7.54 (d, J=6.0 Hz, 4H),7.35-7.20 (m, 11H), 5.97 (s, 1H), 4.49 (s, 2H), 3.81 (b, 2H), 3.49-3.46(m, 6H), 3.31 (s, 2H), 1.99 (bt, J=6.0 Hz, 6H). MS (ESI) m/z caled forC₂₉H₃₄NO₂: 428, found 428 [M+H]⁺.

Example 13 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.20 g, 0.69 mmol) in acetone (30.0 mL) was added((2-bromoethoxy)methyl)benzene (0.16 mL, 1.03 mmol). The reactionmixture was stirred for 24 h at 60° C. Then the reaction mixture wascooled down to 25° C. and concentrated under vacuum, forming a whitesolid. The product was filtered and washed with ethyl acetate (5×20.0mL) and n-hexane (5×20.0 mL) under vacuum. The white solid was thendried under vacuum (0.27 g, 75.7%).

Example 14 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.20 g, 0.69 mmol) in toluene (30.0 mL) was added((2-bromoethoxy)methyl)benzene (0.16 mL, 1.03 mmol). The reactionmixture was stirred for 24 h at 60° C. Then the solution was cooled downto 25° C. and concentrated under vacuum, forming a white solid. Theproduct was filtered and washed with ethyl acetate (5×20.0 mL) andn-hexane (5×20.0 mL) under vacuum. The white solid was then dried undervacuum (0.28 g, 79.6%).

Example 15 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.20 g, 0.69 mmol) in toluene (30.0 mL) was added((2-bromoethoxy)methyl)benzene (0.16 mL, 1.03 mmol). The reactionmixture was stirred for 24 h under reflux. Then the reaction mixture wasslowly cooled down to a temperature between 2° C. and 4° C. wherein awhite solid precipitated. The product was filtered and washed with ethylacetate (5×20.0 mL) and n-hexane (5×20.0 mL) under vacuum. The whitesolid was then dried under vacuum (0.28 g, 79.6%).

Example 16 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.20 g, 0.69 mmol) in water (20.0 mL) was added((2-bromoethoxy)methyl)benzene (0.16 mL, 1.03 mmol). The reactionmixture was stirred for 24 h under reflux. Then the reaction mixture wasslowly cooled down to a temperature between 2° C. and 4° C. wherein awhite solid precipitated. The product was filtered and washed with ethylacetate (20.0 mL) and n-hexane (5×20.0 mL) under vacuum. The white solidwas then dried under vacuum (0.24 g, 68.3%).

Example 17 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.20 g, 0.69 mmol) in water (15.0 mL) and acetone (15.0 mL) was added((2-bromoethoxy)methyl)benzene (0.16 mL, 1.03 mmol). The reactionmixture was stirred for 24 h at 60° C. Then the reaction mixture wasslowly cooled down to a temperature between 2° C. and 4° C. wherein awhite solid precipitated. The product was filtered and washed with ethylacetate (20.0 mL) and n-hexane (5×20.0 mL) under vacuum. The white solidwas then dried under vacuum (0.19 g, 54.2%).

Example 18 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

To a suspension of 1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV,0.75 g, 2.56 mmol) in water (112.50 mL) was added((2-bromoethoxy)methyl)benzene (0.61 mL, 3.83 mmol). The reactionmixture was stirred for 24 h at 60° C. Then the reaction mixture wasslowly cooled down to a temperature between 2° C. and 4° C. and stirredfor 2 h at a temperature between 2° C. and 4° C. The product wasfiltered and washed with ethyl acetate (20.0 mL) and n-hexane (5×20.0mL) under vacuum. The white solid was then dried under vacuum (1.03 g,78.9%).

Example 19 Preparation of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

Triethylamine (5.45 mL, 38.95 mmol) was added to a solution of ethylisonipecotate (4.0 mL, 25.95 mmol) in acetone (43.0 mL) followed by1-bromo-2-chloroethane (4.32 mL, 52.14 mmol). The reaction mixture wasstirred for 17 h at 25° C. n-heptane (43.0 mL) was then added and theacetone was removed under vacuum. To the resultant mixture, n-heptane(43.0 mL) was added again and more acetone was removed under vacuum toobtain a volume of 43.0 mL. Water (43.0 mL) was added to the mixture andextracted with n-heptane (2×43.0 mL). The combined organic layers weredried with MgSO₄, filtered and concentrated under vacuum. This firstcrude product (4.02 g) was analyzed by ¹H-NMR resulting in 1.00:0.11ratio of ethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) todimer. Further n-heptane (11.50 mL) was added to the crude product andthe solution was placed at 0° C. for 1 h and cooled down to −20° C. for16 h. The solid was filtered to remove dimer and then the solution ofethyl 1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) was concentratedunder vacuum. This second crude product (3.57 g) was analyzed by ¹H-NMRresulting in a 1.00:0.09 ratio of ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) to dimer.

A solution of the second crude product (ethyl1-(2-chloroethyl)-4-piperidine-4-carboxylate (II) 3.57 g) in THF (89.6mL) was cooled down to −50° C. under nitrogen. LDA (1.0 M in hexanes/THF20.72 mL, 20.72 mmol) was added to the solution at −50° C. over 25 mins.The reaction mixture was allowed to warm up to room temperature over 16h. The reaction was quenched with saturated aqueous solution of K₂CO₃(74.4 mL) and extracted with ethyl acetate (3×74.4 mL). The combinedorganic layers were dried with MgSO₄, filtered and concentrated undervacuum, to give crude ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate(III) as an orange oil (3.02 g).

A solution of phenyllithium (1.9M in 70 cyclohexane/30 ether, 33.7 mL,64.1 mmol) was cooled down to −30° C., under nitrogen. A solution of thecrude ethyl 1-azabicyclo[2.2.2]octane-4-carboxylate (III, 3.02 g) in THF(36.7 mL) was slowly added to the reaction mixture at −30° C. over 25mins. The reaction mixture was allowed to warm up to room temperatureover 16 h. The reaction was quenched with water (15 mL) and thenevaporated to dryness under vacuum (result: yellow solid). Water (60.2mL) and ethyl acetate (60.2 mL) were added, causing a white solid tocrash out. This solid was filtered off under vacuum, to give crude1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV) as a white powder(1.76 g, three steps yield: 23.0%)

To a suspension of the crude1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol (IV, 1.76 g, 5.83 mmol) inwater (258.0 mL) was added ((2-bromoethoxy)methyl)benzene (1.40 mL, 9.01mmol). The reaction mixture was stirred for 24 h under reflux. Then thereaction mixture was slowly cooled down to a temperature between 2° C.and 4° C. and stirred for 2 h at a temperature between 2° C. and 4° C.The product was filtered under vacuum and excess bromide was removed bywashing the compound with heptane (20.0 mL). The white solid was thendried under vacuum (2.55 g, final step yield 84.0%).

Example 20 Recrystallization of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

A suspension of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I, 0.20 g) in water (2.25 mL) was heated up 80° C. Thesolution was stirred for 1 h then slowly cooled down to a temperaturebetween 2° C. and 4° C. and stirred for 2 h at a temperature between 2°C. and 4° C. The solid was filtered and dried under vacuum (0.185 g,92.5%).

Example 21 Micronization of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I, 3.0 g) was fed to a fluid energy jet mill at 10 g/h,operated with N₂ at a pressure of 4 bar for the venturi and a pressureof 3 bar for the ring.

The isolated product presented an XRPD identical to that of the startingmaterial with a particle size distribution of Dv10=0.664 μm; Dv50=3.071μm; Dv90=7.013 μm; span=2.07, as depicted in FIG. 8.

Example 22 Micronization of4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I)

4-[hydroxyl(diphenyl)methyl]-1-[2(phenylmethyl)oxy]ethyl}-1-azoniabicyclo[2.2.2]octane bromide (I, 15.0 g) was suspended in water (285.0 g) and stirreduntil a uniform suspension was obtained. The uniform suspension was fedto a lab scale High Pressure Homogenization equipment operated at apressure of 60 bar for 100 cycles in total. After the homogenisationstep the suspension was transferred to a holding vessel. The homogenisedsuspension was fed to a lab scale spray dryer whilst stirring at a feedrate of 5.7 ml/min and at a drying temperature of 75° C. (T out).

The isolated product presented an XRPD identical to that of the startingmaterial with a particle size distribution of Dv10=0.55 μm; Dv50=2.10μm; Dv90=4.77 μm; span=2.03, as depicted in FIG. 9.

Instrument Parameters NMR—Nuclear Magnetic Resonance

¹H and ¹³C NMR spectra were recorded on a Bruker 300 Avance at 300 MHz(¹H-NMR) and 75 MHz (¹³C-NMR).

MS—Mass Spectrometry

MS experiments were performed on Micromass® Quattro Micro triplequadrupole (Waters®, Ireland) with an electrospray in positive ion mode(ESI+), ion source at 120° C., capillary voltage of 3.0 kV and sourcevoltage of 30V.

HPLC—High Performance Liquid Chromatography

The HPLC analysis was conducted using a Waters® model Alliance/2695 and2487 detector (dual λ) system under the following conditions:

-   Column: waters symmetry shield RP18 4.6×150 mm 3.5 micra-   Flow rate: 0.8 mL/min-   Injection Volume: 10 uL-   Temperature: 30° C.-   Solvents A: H₂O (0.1% TFA)-   Solvent B: CH₃CN

The gradient elution method as follows:

Time Flow Mobile phase Mobile phase (min.) (mL/min.) A (%) B (%) 0.010.80 85.0 15.0 0.10 0.80 85.0 15.0 36.00 0.80 20.0 80.0 42.00 0.80 20.080.0 42.10 0.80 85.0 15.0 50.00 0.80 85.0 15.0

XRPD—X-Ray Powder Diffraction

The X-ray powder patterns were recorded using the PANalytical X'Pert PROX-ray diffraction system equipped with a copper source (Cu/Kα-1.54056Å).

DSC—Differential Scanning Calorimetry

DSC experiments were performed on DSC Q200, Ramp 10° C./min to 350° C.

TGA—Thermal Gravimetric Analysis

TGA experiments were performed on TGA Q500, Ramp 10° C./min to 350° C.

1. A process comprising: d) reacting1-azabicyclo[2.2.2]oct-4-yl(diphenyl)methanol with((2-bromoethoxy)methyl) benzene in a solvent to form umeclidiniumbromide, wherein the solvent is selected from cyclic ethers, aromaticsolvents, ketones, protic solvents, or combinations thereof.
 2. Theprocess according to claim 1, wherein the cyclic ethers comprisetetrahydrofuran, wherein the aromatic solvents comprise toluene, whereinthe ketones comprise acetone, and wherein the protic solvents comprisewater.
 3. The process according to claim 1, wherein the solvent iswater.
 4. The process according to claim 1, wherein the reaction of stepd) is carried out at a temperature between about 40° C. and about 111°C.
 5. The process according to claim 1, wherein the reaction of step d)is carried out at a temperature between about 60° C. and about 100° C.6. The process according to claim 1, wherein the reaction of step d) iscarried out for a time period of between about 18 h to about 24 h. 7.The process according to claim 1, wherein after some of the umeclidiniumbromide formed in step d) has precipitated from a reaction mixture, theprocess further comprises: cooling down the reaction mixture to atemperature between about −10 ° C. and about 10° C. such that more ofthe umeclidinium bromide formed in step d) precipitates from thereaction mixture.
 8. The process according to claim 7, wherein thereaction mixture is cooled down to a temperature between about 0° C. andabout 5° C.
 9. The process according to claim 8, wherein theprecipitated umeclidinium bromide is filtered and dried to isolate aproduct with a purity ≥98.0% by HPLC.
 10. The process according to claim9, wherein a crystalline form of the isolated umeclidinium bromide is anunsolvated form of umeclidinium bromide.
 11. The process according toclaim 10, wherein the process further comprises: f) micronizing theumeclidinium bromide.
 12. The process according to claim 11, wherein themicronizing is effected by cavitation and/or particle to particlecollision and/or shear stress in a milling apparatus.
 13. The processaccording to claim 12, further comprising the step of isolatingumeclidinium bromide in the form of powder.
 14. The process according toclaim 13, wherein the umeclidinium bromide is isolated by spray drying.15. The process according to claim 1, wherein the process furthercomprises: e) recrystallizing umeclidinium bromide in a second solvent.16. The process according to claim 15, wherein the umeclidinium bromideis recrystallized from the second solvent selected from alcohols, proticsolvents, or combinations thereof.
 17. The process according to claim16, wherein the alcohols comprise 1-propanol and the protic solventscomprise water.
 18. The process according to claim 16, wherein theumeclidinium bromide is recrystallized from water to obtain a productwith a purity ≥99.0% by HPLC.
 19. The process according to claim 15,wherein the recrystallizing of step e) is carried out at a temperaturebetween about 40° C. and about 100° C.
 20. The process according toclaim 15, wherein the recrystallizing of step e) is carried out at atemperature between about 60° C. and about 80° C.
 21. The processaccording to claim 15, wherein step e) comprises cooling down a reactionmixture to a temperature between about −10° C. and about 5° C. to form asuspension.
 22. The process according to claim 21, wherein step e)further comprises stirring the suspension at a temperature between about−10° C. and about 5° C. for about 2 h.
 23. The process according toclaim 1, wherein the process further comprises: f) micronizing theumeclidinium bromide.
 24. The process according to claim 23, wherein themicronizing is effected by cavitation and/or particle to particlecollision and/or shear stress in a milling apparatus.
 25. The processaccording to claim 24, further comprising the step of isolatingumeclidinium bromide in the form of powder.
 26. The process according toclaim 25, wherein the umeclidinium bromide is isolated by spray drying.